Special Issue Information

Dear Colleagues,

The building sector, which includes residential and commercial buildings, is responsible for about one-fifth of the world’s total delivered energy consumption. As the third largest energy consuming sector following the industrial and transportations sectors, the building sector is under increasing pressure to improve its energy efficiency, and to reduce its energy consumption and associated emissions. Thus, the focus of this special issue is on the spectrum of energy technologies, incentive programs and regulatory measures that will result in energy savings and shape the state of energy consumption and efficiency in the building sector in the next decade. Papers that provide a large-scale overview of the various subject areas are sought. Authors are encouraged to address, as much as possible, issues related to the building sectors in both the economically developed and developing nations. The objective of this special issue is to provide an authoritative and archival coverage, therefore only invited papers from leading researchers will be considered for publication.

Abstract: Current office buildings are becoming more and more energy efficient. In particular the importance of heating is decreasing, but the share of electricity use is increasing. When the CO2 equivalent emissions are considered, the CO2 emissions from embodied energy make up an important share of the total, indicating that the building materials have a high importance which is often ignored when only the energy efficiency of running the building is considered. This paper studies a new office building in design phase and offers different alternatives to influence building energy consumption, CO2 equivalent emissions from embodied energy from building materials and CO2 equivalent emissions from energy use and how their relationships should be treated. In addition this paper studies how we should weight the primary energy use and the CO2 equivalent emissions of different design options. The results showed that the reduction of energy use reduces both the primary energy use and CO2 equivalent emissions. Especially the reduction of electricity use has a high importance for both primary energy use and CO2 emissions when fossil fuels are used. The lowest CO2 equivalent emissions were achieved when bio-based, renewable energies or nuclear power was used to supply energy for the office building. Evidently then the share of CO2 equivalent emissions from the embodied energy of building materials and products became the dominant source of CO2 equivalent emissions. The lowest primary energy was achieved when bio-based local heating or renewable energies, in addition to district cooling, were used. The highest primary energy was for the nuclear power option.

Abstract: Typically the aim in the construction process is to calculate the energy, space and cost efficiency in the design phase. These factors’ influence on decision making extends to the whole building process. How these decisions affect the use of the building and user satisfaction as well as maintenance is still not that well understood. This study analyses different schools and day care centers and their energy as well as primary energy use. The buildings are located in southern Finland. Each building has had different objectives with respect to energy efficiency in the design phase. Our objective was to find out how those decisions made in the design and construction phase have influenced the overall energy performance of the building compared to existing building stock of similar building type. The results show that the studied buildings had lower thermal energy consumption compared to existing building stock. Thus the special attention in the design phase allowed achieving the desired goal. However, for the electricity consumption such a correlation could not be found. One of the reasons could be also different service level of buildings (more equipment). Also other quality values could not be compared since such data were not available from the existing building stock. As many earlier studies have indicated users have a high influence on the energy consumption. In the future, when feed-back from the users are obtained it will be interesting to analyze the results and compare what kind of influence that user behavior will have on the overall energy consumption of the studied buildings.

Abstract: In order to estimate the energy consumption demand of residential buildings, this paper first discusses the status and shortcomings of current domestic energy consumption models. Then it proposes and develops a residential building energy consumption demand model based on a back propagation (BP) neural network model. After that, taking residential buildings in Chongqing (P.R. China) as an example, 16 energy consumption indicators are introduced as characteristics of the residential buildings in Chongqing. The index system of the BP neutral network prediction model is established and the multi-factorial BP neural network prediction model of Chongqing residential building energy consumption is developed using the Cshap language, based on the SQL server 2005 platform. The results obtained by applying the model in Chongqing are in good agreement with actual ones. In addition, the model provides corresponding approximate data by taking into account the potential energy structure adjustments and relevant energy policy regulations.